In-situ powerline communication within lithium traction battery cells – Analysis of channel in various configurations

Smart cells—advanced battery units integrated with sensing, communication, and control capabilities—have emerged as a key enabler for next-generation energy storage systems, for improving the cell instrumentation and reducing cable wire harness, Powerline Communication has been validated as deployable in the battery package and Battery Management System without the need for dedicated communication wires. This study focuses on three commonly used cell types in mainstream electric vehicles: Nickel-Manganese-Cobalt, Nickel-Cobalt-Aluminium, and Lithium-Iron-Phosphate. These cells incorporate cathode materials with distinct electrochemical properties, resulting in variations in capacity, charge/discharge behaviour, and impedance, etc. To evaluate the adaptability of Powerline Communication across different cell chemistries, this work investigates Powerline Communication performance across multiple dimensions—including Powerline Communication signal attenuation, signal group delay, cell configuration and cell degradation—within batteries of differing chemistries. Quadrature Phase Shift Keying modulation with carrier frequencies ranging from 5 MHz to 30 MHz is utilised for the Powerline Communication carrier signal, measurements show that this frequency range exhibits minimal signal magnitude attenuation (ranging from 0.025 dB to 0.25 dB) and stable group delay characteristics (approximately 2 ns). Furthermore, after a 200-cycle aging test, only a marginal increase in signal attenuation was observed. The findings indicate that variations in cathode materials in 21700-format cells lead to distinct Powerline Communication channel transfer characteristics and support the use of the 5–30 MHz range as a robust and reliable communication band for smart cell applications. • PLC signal quality varies with battery cathode material. • 5–30 MHz identified as optimal frequency range for cell-level PLC. • BER performance evaluated at different battery SOC levels. • PLC system maintains reliability after long-term cycling.